The expression of the protooncogenes, c‐fos, jun B, c‐jun, and jun D was investigated in a rat focal cerebral ischemia model by Northern analysis and in situ hybridization. Severe ischemia (reduction of regional blood flow by 88‐92%) in this model is confined to cerebral cortex irrigated by the right middle cerebral artery. Ischemia for 30 minutes, which caused only slight cortical damage (infarct size, <10 mm3), induced both jun B and c‐fos mRNAs exclusively in the right cerebral cortex. Ischemia for 90 minutes, which led to large cortical infarction (infarct size, >140 mm3), also induced the expression of these two genes in the right cerebral cortex as well as the ipsilateral hippocampus. The latter sustained very mild ischemia (reduction of regional blood flow by 10–20%). The coinduction of jun B and c‐fos expression occurred immediately after reperfusion and peaked at 60 minutes after reperfusion. The expression of c‐jun was enhanced in a similar pattern, but at a much lower magnitude. In contrast, no change in jun D expression was observed. Nuclear run‐on assays indicated that the increase in c‐fos, jun B, and c‐jun mRNA levels was due to the increase of transcription rate in these genes. Mobility shift assays showed a basal DNA binding activity of transcription factor AP‐1 in the right cerebral cortex. Ischemia for 30 or 90 minutes followed by reperfusion for 4 hours resulted in a four‐ to sixfold increase of AP‐1 binding activity. The enhanced DNA binding activity persisted for as long as 24 hours, These results suggest that the enhanced expression of AP‐1, a general transcription factor, may play a role in the alteration of gene regulation in the ischemic cortex.
Annals of Neurology – Wiley
Published: May 1, 1993
It’s your single place to instantly
discover and read the research
that matters to you.
Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.
All for just $49/month
Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly
Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.
Get unlimited, online access to over 18 million full-text articles from more than 15,000 scientific journals.
Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.
All the latest content is available, no embargo periods.
“Hi guys, I cannot tell you how much I love this resource. Incredible. I really believe you've hit the nail on the head with this site in regards to solving the research-purchase issue.”Daniel C.
“Whoa! It’s like Spotify but for academic articles.”@Phil_Robichaud
“I must say, @deepdyve is a fabulous solution to the independent researcher's problem of #access to #information.”@deepthiw
“My last article couldn't be possible without the platform @deepdyve that makes journal papers cheaper.”@JoseServera